U.S. patent number 11,076,304 [Application Number 16/475,295] was granted by the patent office on 2021-07-27 for communication configuration selection.
This patent grant is currently assigned to Motorola Mobility LLC. The grantee listed for this patent is Motorola Mobility LLC. Invention is credited to Haipeng Lei, Hongchao Li, Xiaodong Yu, Chenxi Zhu.
United States Patent |
11,076,304 |
Li , et al. |
July 27, 2021 |
Communication configuration selection
Abstract
Apparatuses, methods, and systems are disclosed for
communication configuration selection. One apparatus (200) includes
a receiver (212) that receives (602) configuration information for
multiple communication configurations. The configuration
information corresponds to services having different performance
requirements, and the performance requirements include latency,
reliability, peak data rate, efficiency overhead, control overhead,
system capacity, or some combination thereof. The apparatus (200)
also includes a processor (202) that selects (604) a communication
configuration of the multiple communication configurations. The
apparatus (200) communicates (606) using the selected communication
configuration.
Inventors: |
Li; Hongchao (Beijing,
CN), Yu; Xiaodong (Beijing, CN), Lei;
Haipeng (Beijing, CN), Zhu; Chenxi (Fairfax,
VA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Motorola Mobility LLC |
Chicago |
IL |
US |
|
|
Assignee: |
Motorola Mobility LLC (Chicago,
IL)
|
Family
ID: |
1000005701016 |
Appl.
No.: |
16/475,295 |
Filed: |
December 30, 2016 |
PCT
Filed: |
December 30, 2016 |
PCT No.: |
PCT/CN2016/113734 |
371(c)(1),(2),(4) Date: |
July 01, 2019 |
PCT
Pub. No.: |
WO2018/120120 |
PCT
Pub. Date: |
July 05, 2018 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20190342769 A1 |
Nov 7, 2019 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W
8/245 (20130101); H04W 24/02 (20130101) |
Current International
Class: |
H04W
24/02 (20090101); H04W 8/24 (20090101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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102291804 |
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Dec 2011 |
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CN |
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102573072 |
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Jul 2012 |
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CN |
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102685908 |
|
Sep 2012 |
|
CN |
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2011/009271 |
|
Jan 2011 |
|
WO |
|
Other References
PCT/CN2016/113734, "Notification of Transmittal of the
International Search Report and the Written Opinion of the
International Searching Authority, or the Declaration",
International Searching Authority, dated May 27, 2017, pp. 1-10.
cited by applicant .
CMCC, "Discussion on Multiple Access Schemes for URLLC", 3GPP TSG
RAN WG1 Meeting #86bis R1-1609300, Oct. 10-14, 2016, pp. 1-4. cited
by applicant .
CATR, "Discussion on non-orthogonal multiple access for URLLC usage
scenario", 3GPP TSG RAN WG1 Meeting #86bis R1-1609580, Oct. 10-14,
2016, pp. 1-5. cited by applicant .
Sony, "Multiplexing eMBB and URLLC Transmissions", 3GPP TSG RAN WG1
Meeting #86bis R1-1608942, Oct. 10-14, 2016, pp. 1-4. cited by
applicant .
Samsung, "Numerology for URLLC", 3GPP TSG RAN WG1 Meeting #86bis
R1-1609050, Oct. 10-14, 2016, pp. 1-4. cited by applicant .
3GPP, "3rd Generation Partnership Project; Technical Specification
Group Radio Access Network; Study on Scenarios and Requirements for
Next Generation Access Technologies; (Release 14)", 3GPP TR 38.913
V0.4.0, Jun. 2016, pp. 1-35. cited by applicant .
Huawei, Hisilicon, "Support of URLLC in DL", 3GPP TSG RAN WG1
Meeting #86bis R1-1608844, Oct. 10-14, 2016, pp. 1-6. cited by
applicant .
Intel Corporation, "On URLLC mini-slot structure", 3GPP TSG RAN WG1
Meeting #86bis R1-1609510, Oct. 10-14, 2016, pp. 1-5. cited by
applicant .
Qualcomm Incorporated, "URLLC numerology and frame structure
design", 3GPP TSG-RAN WG1 #86bis R1-1610123, Oct. 10-14, 2016, pp.
1-10. cited by applicant .
Huawei, Hisilicon, "WF on URLLC evaluation parameter and LLS
method", 3GPP TSG RAN WG1 Meeting #86 R1-168371, Aug. 22-26, 2016,
pp. 1-6. cited by applicant.
|
Primary Examiner: Jain; Ankur
Attorney, Agent or Firm: Kunzler Bean & Adamson
Claims
The invention claimed is:
1. An apparatus comprising: a receiver that receives configuration
information for a plurality of communication configurations,
wherein the configuration information corresponds to services
having different performance requirements, the configuration
information comprises a frequency bandwidth and a subcarrier
spacing for each communication configuration of the plurality of
communication configurations, the performance requirements comprise
latency, reliability, peak data rate, efficiency overhead, control
overhead, system capacity, or some combination thereof, the
configuration information for each communication configuration of
the plurality of communication configurations comprises a different
set of performance requirements, the configuration information for
each communication configuration of the plurality of communication
configurations corresponds to a different service of the services,
and the services comprise enhanced mobile broad band,
ultra-reliability and low-latency communication, massive machine
type communication, or some combination thereof; and a processor
that selects a communication configuration of the plurality of
communication configurations, wherein the apparatus communicates
using the selected communication configuration.
2. The apparatus of claim 1, wherein the receiver receives the
configuration information via signaling.
3. The apparatus of claim 1, wherein the receiver receives resource
information corresponding to the communication configuration.
4. The apparatus of claim 1, wherein the receiver receives
selection information via signaling for selecting the communication
configuration.
5. The apparatus of claim 1, wherein the processor dynamically
selects the communication configuration.
6. A method comprising: receiving configuration information for a
plurality of communication configurations, wherein the
configuration information corresponds to services having different
performance requirements, the configuration information comprises a
frequency bandwidth and a subcarrier spacing for each communication
configuration of the plurality of communication configurations, the
performance requirements comprise latency, reliability, peak data
rate, efficiency overhead, control overhead, system capacity, or
some combination thereof, the configuration information for each
communication configuration of the plurality of communication
configurations comprises a different set of performance
requirements, the configuration information for each communication
configuration of the plurality of communication configurations
corresponds to a different service of the services, and the
services comprise enhanced mobile broad band, ultra-reliability and
low-latency communication, massive machine type communication, or
some combination thereof; selecting a communication configuration
of the plurality of communication configurations; and communicating
data using the selected communication configuration.
7. The method of claim 6, wherein the communication configuration
comprises an uplink communication configuration corresponding to an
uplink control channel, an uplink data channel, or some combination
thereof.
8. The method of claim 6, wherein the communication configuration
comprises a downlink communication configuration corresponding to a
downlink control channel, a downlink data channel, or some
combination thereof.
9. The method of claim 6, wherein the configuration information
comprises a resource allocation configuration, a transmission mode
configuration, or some combination thereof.
10. An apparatus comprising: a transmitter that transmits
configuration information for a plurality of communication
configurations, wherein the apparatus communicates data using a
selected communication configuration of the plurality of
communication configurations, the configuration information
corresponds to services having different performance requirements,
the configuration information comprises a frequency bandwidth and a
subcarrier spacing for each communication configuration of the
plurality of communication configurations, the performance
requirements comprise latency, reliability, peak data rate,
efficiency overhead, control overhead, system capacity, or some
combination thereof, the configuration information for each
communication configuration of the plurality of communication
configurations comprises a different set of performance
requirements, the configuration information for each communication
configuration of the plurality of communication configurations
corresponds to a different service of the services, and the
services comprise enhanced mobile broad band, ultra-reliability and
low-latency communication, massive machine type communication, or
some combination thereof.
11. The apparatus of claim 10, wherein the transmitter transmits
the configuration information via signaling.
12. The apparatus of claim 10, wherein the transmitter transmits
resource information corresponding to the communication
configuration.
13. The apparatus of claim 10, further comprising a processor that
selects the selected communication configuration.
14. The apparatus of claim 13, wherein the transmitter transmits
information indicating the selected communication
configuration.
15. A method comprising: transmitting configuration information for
a plurality of communication configurations, wherein the
configuration information corresponds to services having different
performance requirements, the configuration information comprises a
frequency bandwidth and a subcarrier spacing for each communication
configuration of the plurality of communication configurations, the
performance requirements comprise latency, reliability, peak data
rate, efficiency overhead, control overhead, system capacity, or
some combination thereof, the configuration information for each
communication configuration of the plurality of communication
configurations comprises a different set of performance
requirements, the configuration information for each communication
configuration of the plurality of communication configurations
corresponds to a different service of the services, and the
services comprise enhanced mobile broad band, ultra-reliability and
low-latency communication, massive machine type communication, or
some combination thereof; and communicating data using a selected
communication configuration of the plurality of communication
configurations.
16. The method of claim 15, wherein the communication configuration
comprises an uplink communication configuration corresponding to an
uplink control channel, an uplink data channel, or some combination
thereof.
17. The method of claim 15, wherein the communication configuration
comprises a downlink communication configuration corresponding to a
downlink control channel, a downlink data channel, or some
combination thereof.
18. The method of claim 15, wherein the configuration information
comprises a resource allocation configuration, a transmission mode
configuration, or some combination thereof.
Description
FIELD
The subject matter disclosed herein relates generally to wireless
communications and more particularly relates to communication
configuration selection.
BACKGROUND
The following abbreviations are herewith defined, at least some of
which are referred to within the following description: Third
Generation Partnership Project ("3GPP"), Positive-Acknowledgment
("ACK"), Binary Phase Shift Keying ("BPSK"), Clear Channel
Assessment ("CCA"), Cyclic Prefix ("CP"), Channel State Information
("CSI"), Common Search Space ("CSS"), Discrete Fourier Transform
Spread ("DFTS"), Downlink Control Information ("DCI"), Downlink
("DL"), Downlink Pilot Time Slot ("DwPTS"), Enhanced Clear Channel
Assessment ("eCCA"), Enhanced Mobile Broadband ("eMBB"), Evolved
Node B ("eNB"), European Telecommunications Standards Institute
("ETSI"), Frame Based Equipment ("FBE"), Frequency Division Duplex
("FDD"), Frequency Division Multiple Access ("FDMA"), Guard Period
("GP"), Hybrid Automatic Repeat Request ("HARQ"),
Internet-of-Things ("IoT"), Licensed Assisted Access ("LAA"), Load
Based Equipment ("LBE"), Listen-Before-Talk ("LBT"), Long Term
Evolution ("LTE"), Multiple Access ("MA"), Modulation Coding Scheme
("MCS"), Machine Type Communication ("MTC"), Multiple Input
Multiple Output ("MIMO"), Multi User Shared Access ("MUSA"),
Narrowband ("NB"), Negative-Acknowledgment ("NACK") or ("NAK"),
Next Generation Node B ("gNB"), Non-Orthogonal Multiple Access
("NOMA"), Orthogonal Frequency Division Multiplexing ("OFDM"),
Primary Cell ("PCell"), Physical Broadcast Channel ("PBCH"),
Physical Downlink Control Channel ("PDCCH"), Physical Downlink
Shared Channel ("PDSCH"), Pattern Division Multiple Access
("PDMA"), Physical Hybrid ARQ Indicator Channel ("PHICH"), Physical
Random Access Channel ("PRACH"), Physical Resource Block ("PRB"),
Physical Uplink Control Channel ("PUCCH"), Physical Uplink Shared
Channel ("PUSCH"), Quality of Service ("QoS"), Quadrature Phase
Shift Keying ("QPSK"), Radio Resource Control ("RRC"), Random
Access Procedure ("RACH"), Random Access Response ("RAR"),
Reference Signal ("RS"), Resource Spread Multiple Access ("RSMA"),
Round Trip Time ("RTT"), Receive ("RX"), Sparse Code Multiple
Access ("SCMA"), Scheduling Request ("SR"), Single Carrier
Frequency Division Multiple Access ("SC-FDMA"), Secondary Cell
("SCell"), Shared Channel ("SCH"),
Signal-to-Interference-Plus-Noise Ratio ("SINR"), System
Information Block ("SIB"), Transport Block ("TB"), Transport Block
Size ("TBS"), Time-Division Duplex ("TDD"), Time Division Multiplex
("TDM"), Transmission Time Interval ("TTI"), Transmit ("TX"),
Uplink Control Information ("UCI"), User Entity/Equipment (Mobile
Terminal) ("UE"), Uplink ("UL"), Universal Mobile
Telecommunications System ("UMTS"), Uplink Pilot Time Slot
("UpPTS"), Ultra-reliability and Low-latency Communications
("URLLC"), and Worldwide Interoperability for Microwave Access
("WiMAX"). As used herein, "HARQ-ACK" may represent collectively
the Positive Acknowledge ("ACK") and the Negative Acknowledge
("NAK"). ACK means that a TB is correctly received while NAK means
a TB is erroneously received.
In certain wireless communications networks, URLLC may have a data
payload that is small. According to some circumstances, URLLC may
have a periodically occurring packet arrival rate and a packet size
may be 32 bytes, 50 bytes, 200 bytes, and so forth. In some other
circumstances, URLLC may have sporadically occurring packets with
large or small packet size.
In certain configurations, for URLLC, the user plane latency may be
0.5 ms for UL, and 0.5 ms for DL. Moreover, URLLC reliability may
be evaluated by a success probability of transmitting X bytes
within 1 ms. This may be the time it takes to deliver a small data
packet from the radio protocol layer 2/3 service data unit ("SDU")
ingress point to the radio protocol layer 2/3 SDU egress point of
the radio interface, at a certain channel quality (e.g.,
coverage-edge). In various configurations, the target for
reliability may be 1-10.sup.-s within 1 ms. In certain
configurations, a general URLLC reliability requirement for one
transmission of a packet may be 1-10-5 for X bytes (e.g., 20 bytes)
with a user plane latency of 1 ms.
BRIEF SUMMARY
Apparatuses for communication configuration selection are
disclosed. Methods and systems also perform the functions of the
apparatus. In one embodiment, the apparatus includes a receiver
that receives configuration information for multiple communication
configurations. In various embodiments, the configuration
information corresponds to services having different performance
requirements, and the performance requirements include latency,
reliability, peak data rate, efficiency overhead, control overhead,
system capacity, or some combination thereof. The apparatus also
includes a processor that selects a communication configuration of
the multiple communication configurations. In certain embodiments,
the apparatus communicates using the selected communication
configuration.
In one embodiment, the resource granularity configuration
information includes a time duration, a frequency bandwidth, a
subcarrier spacing, a waveform, a reference signal pattern, a
cyclic prefix overhead setting, or some combination thereof for
each communication configuration of the multiple communication
configurations. In a further embodiment, the receiver receives the
configuration information via signaling. In certain embodiments,
the receiver receives resource information corresponding to the
communication configuration. In some embodiments, the multiple
communication configurations include communication configurations
selected from the group including enhanced mobile broad band, ultra
reliable and low latency communication, and massive machine type
communication.
In various embodiments, the receiver receives selection information
via signaling for selecting the communication configuration. In
some embodiments, the processor dynamically selects the
communication configuration. In one embodiment, the communication
configuration includes an uplink communication configuration
corresponding to an uplink control channel, an uplink data channel,
or some combination thereof. In a further embodiment, the
communication configuration includes a downlink communication
configuration corresponding to a downlink control channel, a
downlink data channel, or some combination thereof. In various
embodiments, the configuration information includes a resource
allocation configuration, a transmission mode configuration, or
some combination thereof.
A method for communication configuration selection, in one
embodiment, includes receiving configuration information for
multiple communication configurations. In certain embodiments, the
configuration information corresponds to services having different
performance requirements, and the performance requirements include
latency, reliability, peak data rate, efficiency overhead, control
overhead, system capacity, or some combination thereof. The method
also includes selecting a communication configuration of the
multiple communication configurations. The method includes
communicating data using the selected communication
configuration.
In one embodiment, an apparatus includes a transmitter that
transmits configuration information for multiple communication
configurations. In various embodiments, the apparatus communicates
data using a selected communication configuration of the multiple
communication configurations, the configuration information
corresponds to services having different performance requirements,
and the performance requirements include latency, reliability, peak
data rate, efficiency overhead, control overhead, system capacity,
or some combination thereof.
In one embodiment, the configuration information includes a time
duration, a frequency bandwidth, a subcarrier spacing, a waveform,
a reference signal pattern, a cyclic prefix overhead setting, or
some combination thereof for each communication configuration of
the multiple communication configurations. In a further embodiment,
the transmitter transmits the configuration information via
signaling. In certain embodiments, the transmitter transmits
resource information corresponding to the communication
configuration. In some embodiments, the multiple communication
configurations include communication configurations selected from
the group including enhanced mobile broad band, ultra reliable and
low latency communication, and massive machine type
communication.
In various embodiments, the apparatus includes a processor that
selects the selected communication configuration. In some
embodiments, the transmitter transmits information indicating the
selected communication configuration. In one embodiment, the
communication configuration includes an uplink communication
configuration corresponding to an uplink control channel, an uplink
data channel, or some combination thereof. In a further embodiment,
the communication configuration includes a downlink communication
configuration corresponding to a downlink control channel, a
downlink data channel, or some combination thereof. In various
embodiments, the configuration information includes a resource
allocation configuration, a transmission mode configuration, or
some combination thereof.
A method for communication configuration selection, in one
embodiment, includes transmitting configuration information for
multiple communication configurations. In certain embodiments, the
configuration information corresponds to services having different
performance requirements, and the performance requirements include
latency, reliability, peak data rate, efficiency overhead, control
overhead, system capacity, or some combination thereof. The method
also includes communicating data using a selected communication
configuration of the multiple communication configurations.
BRIEF DESCRIPTION OF THE DRAWINGS
A more particular description of the embodiments briefly described
above will be rendered by reference to specific embodiments that
are illustrated in the appended drawings. Understanding that these
drawings depict only some embodiments and are not therefore to be
considered to be limiting of scope, the embodiments will be
described and explained with additional specificity and detail
through the use of the accompanying drawings, in which:
FIG. 1 is a schematic block diagram illustrating one embodiment of
a wireless communication system for communication configuration
selection;
FIG. 2 is a schematic block diagram illustrating one embodiment of
an apparatus that may be used for communication configuration
selection;
FIG. 3 is a schematic block diagram illustrating one embodiment of
an apparatus that may be used for communication configuration
selection;
FIG. 4 illustrates one embodiment of communications for
communication configuration selection;
FIG. 5 is a schematic block diagram illustrating one embodiment of
communications for communication configuration selection;
FIG. 6 is a schematic flow chart diagram illustrating one
embodiment of a method for communication configuration selection;
and
FIG. 7 is a schematic flow chart diagram illustrating another
embodiment of a method for communication configuration
selection.
DETAILED DESCRIPTION
As will be appreciated by one skilled in the art, aspects of the
embodiments may be embodied as a system, apparatus, method, or
program product. Accordingly, embodiments may take the form of an
entirely hardware embodiment, an entirely software embodiment
(including firmware, resident software, micro-code, etc.) or an
embodiment combining software and hardware aspects that may all
generally be referred to herein as a "circuit," "module" or
"system." Furthermore, embodiments may take the form of a program
product embodied in one or more computer readable storage devices
storing machine readable code, computer readable code, and/or
program code, referred hereafter as code. The storage devices may
be tangible, non-transitory, and/or non-transmission. The storage
devices may not embody signals. In a certain embodiment, the
storage devices only employ signals for accessing code.
Certain of the functional units described in this specification may
be labeled as modules, in order to more particularly emphasize
their implementation independence. For example, a module may be
implemented as a hardware circuit comprising custom
very-large-scale integration ("VLSI") circuits or gate arrays,
off-the-shelf semiconductors such as logic chips, transistors, or
other discrete components. A module may also be implemented in
programmable hardware devices such as field programmable gate
arrays, programmable array logic, programmable logic devices or the
like.
Modules may also be implemented in code and/or software for
execution by various types of processors. An identified module of
code may, for instance, include one or more physical or logical
blocks of executable code which may, for instance, be organized as
an object, procedure, or function. Nevertheless, the executables of
an identified module need not be physically located together, but
may include disparate instructions stored in different locations
which, when joined logically together, include the module and
achieve the stated purpose for the module.
Indeed, a module of code may be a single instruction, or many
instructions, and may even be distributed over several different
code segments, among different programs, and across several memory
devices. Similarly, operational data may be identified and
illustrated herein within modules, and may be embodied in any
suitable form and organized within any suitable type of data
structure. The operational data may be collected as a single data
set, or may be distributed over different locations including over
different computer readable storage devices. Where a module or
portions of a module are implemented in software, the software
portions are stored on one or more computer readable storage
devices.
Any combination of one or more computer readable medium may be
utilized. The computer readable medium may be a computer readable
storage medium. The computer readable storage medium may be a
storage device storing the code. The storage device may be, for
example, but not limited to, an electronic, magnetic, optical,
electromagnetic, infrared, holographic, micromechanical, or
semiconductor system, apparatus, or device, or any suitable
combination of the foregoing.
More specific examples (a non-exhaustive list) of the storage
device would include the following: an electrical connection having
one or more wires, a portable computer diskette, a hard disk, a
random access memory ("RAM"), a read-only memory ("ROM"), an
erasable programmable read-only memory ("EPROM" or Flash memory), a
portable compact disc read-only memory ("CD-ROM"), an optical
storage device, a magnetic storage device, or any suitable
combination of the foregoing. In the context of this document, a
computer readable storage medium may be any tangible medium that
can contain, or store a program for use by or in connection with an
instruction execution system, apparatus, or device.
Code for carrying out operations for embodiments may be any number
of lines and may be written in any combination of one or more
programming languages including an object oriented programming
language such as Python, Ruby, Java, Smalltalk, C++, or the like,
and conventional procedural programming languages, such as the "C"
programming language, or the like, and/or machine languages such as
assembly languages. The code may execute entirely on the user's
computer, partly on the user's computer, as a stand-alone software
package, partly on the user's computer and partly on a remote
computer or entirely on the remote computer or server. In the
latter scenario, the remote computer may be connected to the user's
computer through any type of network, including a local area
network ("LAN") or a wide area network ("WAN"), or the connection
may be made to an external computer (for example, through the
Internet using an Internet Service Provider).
Reference throughout this specification to "one embodiment," "an
embodiment," or similar language means that a particular feature,
structure, or characteristic described in connection with the
embodiment is included in at least one embodiment. Thus,
appearances of the phrases "in one embodiment," "in an embodiment,"
and similar language throughout this specification may, but do not
necessarily, all refer to the same embodiment, but mean "one or
more but not all embodiments" unless expressly specified otherwise.
The terms "including," "comprising," "having," and variations
thereof mean "including but not limited to," unless expressly
specified otherwise. An enumerated listing of items does not imply
that any or all of the items are mutually exclusive, unless
expressly specified otherwise. The terms "a," "an," and "the" also
refer to "one or more" unless expressly specified otherwise.
Furthermore, the described features, structures, or characteristics
of the embodiments may be combined in any suitable manner. In the
following description, numerous specific details are provided, such
as examples of programming, software modules, user selections,
network transactions, database queries, database structures,
hardware modules, hardware circuits, hardware chips, etc., to
provide a thorough understanding of embodiments. One skilled in the
relevant art will recognize, however, that embodiments may be
practiced without one or more of the specific details, or with
other methods, components, materials, and so forth. In other
instances, well-known structures, materials, or operations are not
shown or described in detail to avoid obscuring aspects of an
embodiment.
Aspects of the embodiments are described below with reference to
schematic flowchart diagrams and/or schematic block diagrams of
methods, apparatuses, systems, and program products according to
embodiments. It will be understood that each block of the schematic
flowchart diagrams and/or schematic block diagrams, and
combinations of blocks in the schematic flowchart diagrams and/or
schematic block diagrams, can be implemented by code. These code
may be provided to a processor of a general purpose computer,
special purpose computer, or other programmable data processing
apparatus to produce a machine, such that the instructions, which
execute via the processor of the computer or other programmable
data processing apparatus, create means for implementing the
functions/acts specified in the schematic flowchart diagrams and/or
schematic block diagrams block or blocks.
The code may also be stored in a storage device that can direct a
computer, other programmable data processing apparatus, or other
devices to function in a particular manner, such that the
instructions stored in the storage device produce an article of
manufacture including instructions which implement the function/act
specified in the schematic flowchart diagrams and/or schematic
block diagrams block or blocks.
The code may also be loaded onto a computer, other programmable
data processing apparatus, or other devices to cause a series of
operational steps to be performed on the computer, other
programmable apparatus or other devices to produce a computer
implemented process such that the code which execute on the
computer or other programmable apparatus provide processes for
implementing the functions/acts specified in the flowchart and/or
block diagram block or blocks.
The schematic flowchart diagrams and/or schematic block diagrams in
the Figures illustrate the architecture, functionality, and
operation of possible implementations of apparatuses, systems,
methods and program products according to various embodiments. In
this regard, each block in the schematic flowchart diagrams and/or
schematic block diagrams may represent a module, segment, or
portion of code, which includes one or more executable instructions
of the code for implementing the specified logical function(s).
It should also be noted that, in some alternative implementations,
the functions noted in the block may occur out of the order noted
in the Figures. For example, two blocks shown in succession may, in
fact, be executed substantially concurrently, or the blocks may
sometimes be executed in the reverse order, depending upon the
functionality involved. Other steps and methods may be conceived
that are equivalent in function, logic, or effect to one or more
blocks, or portions thereof, of the illustrated Figures.
Although various arrow types and line types may be employed in the
flowchart and/or block diagrams, they are understood not to limit
the scope of the corresponding embodiments. Indeed, some arrows or
other connectors may be used to indicate only the logical flow of
the depicted embodiment. For instance, an arrow may indicate a
waiting or monitoring period of unspecified duration between
enumerated steps of the depicted embodiment. It will also be noted
that each block of the block diagrams and/or flowchart diagrams,
and combinations of blocks in the block diagrams and/or flowchart
diagrams, can be implemented by special purpose hardware-based
systems that perform the specified functions or acts, or
combinations of special purpose hardware and code.
The description of elements in each figure may refer to elements of
proceeding figures. Like numbers refer to like elements in all
figures, including alternate embodiments of like elements.
FIG. 1 depicts an embodiment of a wireless communication system 100
for communication configuration selection. In one embodiment, the
wireless communication system 100 includes remote units 102 and
base units 104. Even though a specific number of remote units 102
and base units 104 are depicted in FIG. 1, one of skill in the art
will recognize that any number of remote units 102 and base units
104 may be included in the wireless communication system 100.
In one embodiment, the remote units 102 may include computing
devices, such as desktop computers, laptop computers, personal
digital assistants ("PDAs"), tablet computers, smart phones, smart
televisions (e.g., televisions connected to the Internet), set-top
boxes, game consoles, security systems (including security
cameras), vehicle on-board computers, network devices (e.g.,
routers, switches, modems), or the like. In some embodiments, the
remote units 102 include wearable devices, such as smart watches,
fitness bands, optical head-mounted displays, or the like.
Moreover, the remote units 102 may be referred to as subscriber
units, mobiles, mobile stations, users, terminals, mobile
terminals, fixed terminals, subscriber stations, UE, user
terminals, a device, or by other terminology used in the art. The
remote units 102 may communicate directly with one or more of the
base units 104 via UL communication signals.
The base units 104 may be distributed over a geographic region. In
certain embodiments, a base unit 104 may also be referred to as an
access point, an access terminal, a base, a base station, a Node-B,
an eNB, a gNB, a Home Node-B, a relay node, a device, or by any
other terminology used in the art. The base units 104 are generally
part of a radio access network that includes one or more
controllers communicably coupled to one or more corresponding base
units 104. The radio access network is generally communicably
coupled to one or more core networks, which may be coupled to other
networks, like the Internet and public switched telephone networks,
among other networks. These and other elements of radio access and
core networks are not illustrated but are well known generally by
those having ordinary skill in the art.
In one implementation, the wireless communication system 100 is
compliant with the LTE of the 3GPP protocol, wherein the base unit
104 transmits using an OFDM modulation scheme on the DL and the
remote units 102 transmit on the UL using a SC-FDMA scheme or an
OFDM scheme. More generally, however, the wireless communication
system 100 may implement some other open or proprietary
communication protocol, for example, WiMAX, among other protocols.
The present disclosure is not intended to be limited to the
implementation of any particular wireless communication system
architecture or protocol.
The base units 104 may serve a number of remote units 102 within a
serving area, for example, a cell or a cell sector via a wireless
communication link. The base units 104 transmit DL communication
signals to serve the remote units 102 in the time, frequency,
and/or spatial domain.
In one embodiment, a base unit 104 may transmit configuration
information for multiple communication configurations. The
configuration information may correspond to services having
different performance requirements, and the performance
requirements may include latency, reliability, peak data rate,
efficiency overhead, control overhead, system capacity, or some
combination thereof. In some embodiments, the base unit 104 may
communicate data using a selected communication configuration of
the multiple communication configurations. Accordingly, a base unit
104 may be used for communication configuration selection.
In another embodiment, a remote unit 102 may receive configuration
information for multiple communication configurations. The
configuration information may correspond to services having
different performance requirements, and the performance
requirements may include latency, reliability, peak data rate,
efficiency overhead, control overhead, system capacity, or some
combination thereof. The remote unit 102 may select a communication
configuration of the multiple communication configurations. The
remote unit 102 may communicate data using the selected
communication configuration. Accordingly, a remote unit 102 may be
used for communication configuration selection.
FIG. 2 depicts one embodiment of an apparatus 200 that may be used
for communication configuration selection. The apparatus 200
includes one embodiment of the remote unit 102. Furthermore, the
remote unit 102 may include a processor 202, a memory 204, an input
device 206, a display 208, a transmitter 210, and a receiver 212.
In some embodiments, the input device 206 and the display 208 are
combined into a single device, such as a touchscreen. In certain
embodiments, the remote unit 102 may not include any input device
206 and/or display 208. In various embodiments, the remote unit 102
may include one or more of the processor 202, the memory 204, the
transmitter 210, and the receiver 212, and may not include the
input device 206 and/or the display 208.
The processor 202, in one embodiment, may include any known
controller capable of executing computer-readable instructions
and/or capable of performing logical operations. For example, the
processor 202 may be a microcontroller, a microprocessor, a central
processing unit ("CPU"), a graphics processing unit ("GPU"), an
auxiliary processing unit, a field programmable gate array
("FPGA"), or similar programmable controller. In some embodiments,
the processor 202 executes instructions stored in the memory 204 to
perform the methods and routines described herein. In certain
embodiments, the processor 202 may select a communication
configuration of multiple communication configurations. In various
embodiments, the processor 202 facilitates communication using the
selected communication configuration. The processor 202 is
communicatively coupled to the memory 204, the input device 206,
the display 208, the transmitter 210, and the receiver 212.
The memory 204, in one embodiment, is a computer readable storage
medium. In some embodiments, the memory 204 includes volatile
computer storage media. For example, the memory 204 may include a
RAM, including dynamic RAM ("DRAM"), synchronous dynamic RAM
("SDRAM"), and/or static RAM ("SRAM"). In some embodiments, the
memory 204 includes non-volatile computer storage media. For
example, the memory 204 may include a hard disk drive, a flash
memory, or any other suitable non-volatile computer storage device.
In some embodiments, the memory 204 includes both volatile and
non-volatile computer storage media. In some embodiments, the
memory 204 stores data relating to communication configurations. In
some embodiments, the memory 204 also stores program code and
related data, such as an operating system or other controller
algorithms operating on the remote unit 102.
The input device 206, in one embodiment, may include any known
computer input device including a touch panel, a button, a
keyboard, a stylus, a microphone, or the like. In some embodiments,
the input device 206 may be integrated with the display 208, for
example, as a touchscreen or similar touch-sensitive display. In
some embodiments, the input device 206 includes a touchscreen such
that text may be input using a virtual keyboard displayed on the
touchscreen and/or by handwriting on the touchscreen. In some
embodiments, the input device 206 includes two or more different
devices, such as a keyboard and a touch panel.
The display 208, in one embodiment, may include any known
electronically controllable display or display device. The display
208 may be designed to output visual, audible, and/or haptic
signals. In some embodiments, the display 208 includes an
electronic display capable of outputting visual data to a user. For
example, the display 208 may include, but is not limited to, an LCD
display, an LED display, an OLED display, a projector, or similar
display device capable of outputting images, text, or the like to a
user. As another, non-limiting, example, the display 208 may
include a wearable display such as a smart watch, smart glasses, a
heads-up display, or the like. Further, the display 208 may be a
component of a smart phone, a personal digital assistant, a
television, a table computer, a notebook (laptop) computer, a
personal computer, a vehicle dashboard, or the like.
In certain embodiments, the display 208 includes one or more
speakers for producing sound. For example, the display 208 may
produce an audible alert or notification (e.g., a beep or chime).
In some embodiments, the display 208 includes one or more haptic
devices for producing vibrations, motion, or other haptic feedback.
In some embodiments, all or portions of the display 208 may be
integrated with the input device 206. For example, the input device
206 and display 208 may form a touchscreen or similar
touch-sensitive display. In other embodiments, the display 208 may
be located near the input device 206.
The transmitter 210 is used to provide UL communication signals to
the base unit 104 and the receiver 212 is used to receive DL
communication signals from the base unit 104. In one embodiment,
the receiver 212 may be used to receive configuration information
for multiple communication configurations. The configuration
information may correspond to services having different performance
requirements, and the performance requirements may include latency,
reliability, peak data rate, efficiency overhead, control overhead,
system capacity, or some combination thereof. Although only one
transmitter 210 and one receiver 212 are illustrated, the remote
unit 102 may have any suitable number of transmitters 210 and
receivers 212. The transmitter 210 and the receiver 212 may be any
suitable type of transmitters and receivers. In one embodiment, the
transmitter 210 and the receiver 212 may be part of a
transceiver.
FIG. 3 depicts one embodiment of an apparatus 300 that may be used
for communication configuration selection. The apparatus 300
includes one embodiment of the base unit 104. Furthermore, the base
unit 104 may include a processor 302, a memory 304, an input device
306, a display 308, a transmitter 310, and a receiver 312. As may
be appreciated, the processor 302, the memory 304, the input device
306, the display 308, the transmitter 310, and the receiver 312 may
be substantially similar to the processor 202, the memory 204, the
input device 206, the display 208, the transmitter 210, and the
receiver 212 of the remote unit 102, respectively.
In various embodiment, the transmitter 310 is used to transmit
configuration information for multiple communication
configurations. In some embodiments, the configuration information
corresponds to services having different performance requirements,
and the performance requirements may include latency, reliability,
peak data rate, efficiency overhead, control overhead, system
capacity, or some combination thereof. In certain embodiments, the
processor 302 may facilitate communicating data using a selected
communication configuration of the multiple communication
configurations. Although only one transmitter 310 and one receiver
312 are illustrated, the base unit 104 may have any suitable number
of transmitters 310 and receivers 312. The transmitter 310 and the
receiver 312 may be any suitable type of transmitters and
receivers. In one embodiment, the transmitter 310 and the receiver
312 may be part of a transceiver.
FIG. 4 illustrates one embodiment of communications 400 for
communication configuration selection. Specifically, communications
400 between a first UE 402, a second UE 404, and a gNB 406 are
illustrated. The communications 400 may facilitate flexibly
scheduling eMBB and URLLC. To facilitate flexibly scheduling eMBB
and URLLC, a flexible resource granularity shaping indication
and/or configuration mechanism may be used.
In one embodiment, a set of usable resource granularities may be
configured to the first UE 402 and/or the second UE 404 (and/or
other UEs) via RRC signaling. The resource granularity candidates
may provide multiple options which may have a minimum scheduling
granularity. Each resource granularity candidate may be represented
by a time domain length (e.g. M OFDM symbols, X ms, X us, etc.)
and/or a frequency domain bandwidth (e.g. N subcarriers, etc.). In
some embodiments, the resource granularity candidates may include a
limited set of options for a network to choose based on use cases
and/or services that are currently running and/or may be operating.
In various embodiments, certain corresponding desirable performance
requirements may be considered.
In certain embodiments, a resource granularity candidate may be
associated with a waveform (e.g., CP-OFDM, SC-FDMA), numerology,
and/or CP length setting, each of which may be a default (e.g., as
used by a synchronization signal block, a primary synchronization
signal block, a secondary synchronization signal, and so forth), a
scaled setting, and/or a configurable setting.
In one embodiment, each resource granularity candidate may include
a reference signal pattern based on a shaping and/or a targeted
application scenario (e.g., large blocks of resources may be used
to schedule eMBB traffic, one symbol scheduling/triggering may be
used for URLLC traffic, single-tone scheduling may be used for
coverage enhancement and low cost mMTC UEs for a specific MIMO
scheme).
In various embodiments, the resource granularity candidate may be
used to indicate: a DL control channel resource subset for a
certain UE; a DL data channel resource location for a certain UE;
an UL data channel resource location for a certain UE; an UL
control channel resource location for a certain UE; and/or a
minimum resource unit containing a UL grant-free transmission
within or without a resource pool constraint. In some embodiments,
at least one of the resource granularity candidates may support a
spreading/interleaving-based NOMA scheme.
In various embodiments, a resource granularity candidate that is
used for a certain channel or transmission may be dynamically
indicated, selected, and/or changed by physical control signaling
(e.g., DCI) and/or may be semi-statically configured via a
broadcast message, a common channel, and/or common signaling. In
one embodiment, based on the resource granularity candidate to be
used, the gNB 406 may efficiently schedule a transport block or
coding blocks to appropriate physical resources.
In certain embodiments, UL URLLC may be based on grant-free
transmission and may be configured with a resource that may be
selectively scheduled to UL eMBB transmission. Thus, the resource
allocation for grant-free transmission may employ a granularity
shaping framework that facilitates introducing less impact to eMBB.
In various embodiments, a resource granularity candidate used by
URLLC may be smaller than that used by one coding block ("CB") of
eMBB as illustrated by FIG. 5.
Turning to FIG. 5, a schematic block diagram illustrating one
embodiment of communications 500 for communication configuration
selection is shown. Specifically, the communications 500 include an
eMBB TB 502 that includes four eMBB CBs 504. Indeed, the eMBB TB
502 includes a first eMBB CB 506, a second eMBB CB 508, a third
eMBB CB 510, and a fourth eMBB CB 512. Moreover, a first URLLC
communication 514 is multiplexed with the second eMBB CB 508, and a
second URLLC communication 516 is multiplexed with the fourth eMBB
CB 512.
Returning to FIG. 4, a first communication 408 may include a
message sent from the gNB 406 to the first UE 402 indicating one or
more resource granularity candidates (e.g., such as the resource
granularity candidates shown in Table 1), such as via RRC
signaling. Moreover, a second communication 410 may include a
message sent from the gNB 406 to the second UE 404 indicating the
one or more resource granularity candidates (e.g., such as the
resource granularity candidates shown in Table 1), such as via RRC
signaling.
TABLE-US-00001 TABLE 1 Granularity Time Frequency Sub- Shaping
Domain Domain carrier Index Duration Bandwidth Spacing Waveform 00
7 OFDM 12 Subcarriers 15 kHz OFDM Symbols 01 1 OFDM 168 Subcarriers
30 kHz OFDM Symbol 10 168 Symbols 1 Subcarrier 15 kHz Single-Tone
11 2 Symbols 42 Subcarriers 15 kHz DFTS- OFDM
In one embodiment, the gNB 406 may configure available resource
granularity candidates based on the service types that are and/or
will be used. For example, the granularity shaping index `00` may
be used for generic eMBB traffic scheduling; the granularity
shaping index `01` may be used for URLLC traffic scheduling and/or
grant-free transmission as possessing short transmission duration;
the granularity shaping index `10` may be used by mMTC because of
its single carrier property and because coverage enhancement may be
achieved by using high power density; the granularity shaping index
`11` may be used for more balanced granularity shaping with the
DFTS-OFDM waveform (e.g., which may be used for both eMBB and URLLC
services and some coverage limited use cases).
A third communication 412 may include a message transmitted from
the gNB 406 to the second UE 404 to indicate to the second UE 404
usable UL grant-free transmission opportunities for URLLC traffic.
The indication may include a minimum resource granularity (e.g.,
granularity shaping index `01`), and allowed resource mapping
positions. In various embodiments, a resource granularity candidate
used by URLLC may be smaller than that used by one coding block
("CB") of eMBB. In some embodiments, a URLLC transmission
opportunity may avoid overlapping with the RS used by eMBB
transmission. In the present embodiment, an eMBB transport block
may include four CBs without CB level interleaving, as illustrated
in FIG. 5.
A fourth communication 414 may include a message transmitted from
the gNB 404 to the first UE 402 to schedule UL resource for eMBB
traffic. The message may be transmitted by physical layer control
signaling. In one embodiment, the message includes the resource
granularity shaping index field of `00` and resources are allocated
for concatenated coding blocks.
A fifth communication 416 may include messages sent from the second
UE 404 to the gNB 406. Specifically, in response to URLLC traffic
arriving driven by a service running in the second UE 404, the
second UE 404 may begin grant-free transmission and choose the
resource granularity shaping and opportunities that are configured
by the second communication 410. In certain embodiments, the
transmission starting opportunity may have a property that an
overlapping resource between eMBB and URLLC impacts no more than
one CB of eMBB, which may also be configured by the second
communication 410.
In certain embodiments, the gNB 406 may decode eMBB CBs and then
TBs with the pre-knowledge of the potential presence of URLLC
transmission in a grant-free manner. In various embodiments, the
gNB 406 may first prioritize the demodulation and decoding of the
URLLC traffic, then prioritize the eMBB CBs without interference
from URLLC traffic, and then prioritize the eMBB CBs possibly
interfered by URLLC packet. In some embodiments, the eMBB
transmission from the first UE 402 may be URLLC transmission, with
a latency requirement that is more relaxed than the URLLC
transmission from the second UE 404. It should be noted that a
resource granularity shaping framework may apply to UL, DL, and/or
UL control channel. As the requirement for UL control channel in
different scenarios may be different, the UL control channel format
used by a certain service may also be flexibly defined and
triggered.
In another example, UL control channels with different resource
granularity shaping options and waveform options may be used.
Depending on the application and intended function to be performed,
different UL control channel shaping may carry different type of
UCIs.
In certain embodiments, the gNB 406 may configure 2 UL control
channel resource granularity shaping options via RRC signaling, as
illustrated in Table 2. The granularity shaping index `0`
represents a relatively longer duration and narrower bandwidth with
DFTS-OFDM waveform and may have better coverage performance than
the granularity shaping index `1`. In addition, the granularity
shaping index `0` may be friendlier to a DL eMBB service because
the UCI may be feedback in a longer interval (e.g., the whole slot
duration in FIG. 2 may be too long to support eMBB traffic and the
UL control part may have a long enough duration to achieve better
energy accumulation for better UL control channel performance). On
the other hand, the granularity shaping index `1` may be applicable
to scenarios that require short latency.
TABLE-US-00002 TABLE 2 Granularity Time Frequency Sub- Shaping
Domain Domain carrier Index Duration Bandwidth Spacing Waveform 0 4
Symbols 36 Subcarriers 15 kHz DTFS- OFDM 1 1 Symbol.sup. 144
Subcarriers 30 kHz OFDM
In one embodiment, the first UE 402 may be scheduled with DL eMBB
traffic with high data rate. The slot duration used for scheduling
the first UE 402 may be quite long which is achieved by
slot-aggregation. The UCI (e.g., including HARQ ACK/NACK, CSI,
etc.) transmitted in the UL symbols may use the granularity shaping
index `0` in Table 2 and the indication to use the granularity
shaping index `0` may be delivered to the first UE 402 in DL
physical layer control signaling.
During a DL eMBB transmission for the first UE 402, the first UE
402 may be scheduled with a one-shot URLLC DL packet generated by a
low latency service. In this case, the gNB 406 may indicate to the
first UE 402 the usable UL control channel resource granularity or
may indicate to the first UE 402 to use the granularity shaping
index `1` via physical layer control signaling, which may be used
to carry ACK/NACK feedback.
After decoding the URLLC packet from the gNB 406, the first UE 402
may provide feedback ACK/NACK according to the indication from the
gNB 406 relating to resource location and channel resource
granularity. If the indicated resource overlaps and/or collides
with the resource used by UCI of DL eMBB traffic, the first UE 402
may choose to postpone, puncture, and/or rate match around the
resource when mapping the UCI for DL eMBB traffic. Thus, the
behavior of the first UE 402 may be aligned with the gNB 406.
After receiving ACK from the first UE 402, the gNB 406 may proceed
with a URLLC high layer procedure to accomplish an air interface
procedure as soon as possible to achieve low end to end latency. In
some embodiments, the multiplexing between UL control channel for
URLLC and eMBB may also happen for two different UEs (e.g., the
first UE 402 and the second UE 404). The procedures may be
substantially the same for the two different UEs. In certain
embodiments, the adjustment of the UCI mapping for eMBB may depend
on whether the eMBB UE can acquire the URLLC scheduling and
ACK/NACK feedback related information.
In various embodiments, resource granularity candidates may include
information for communication: without CB interleaving, with CB
interleaving, via DL, via UL, via TDD, via FDD, and/or via UL
control channel.
FIG. 6 is a schematic flow chart diagram illustrating one
embodiment of a method 600 for communication configuration
selection. In some embodiments, the method 600 is performed by an
apparatus, such as the remote unit 102. In certain embodiments, the
method 600 may be performed by a processor executing program code,
for example, a microcontroller, a microprocessor, a CPU, a GPU, an
auxiliary processing unit, a FPGA, or the like.
The method 600 may include receiving 602 configuration information
for multiple communication configurations (e.g., such as shown in
Tables 1 and 2). The configuration information may correspond to
services (e.g., eMBB, URLLC, MMC) having different performance
requirements, and the performance requirements may include latency,
reliability, peak data rate, efficiency overhead, control overhead,
system capacity, or some combination thereof. The method 600 also
includes selecting 604 a communication configuration of the
multiple communication configurations. In one embodiment, the
method 600 includes communicating 606 (e.g., transmitting and/or
receiving) data using the selected communication configuration.
In one embodiment, the configuration information includes a time
duration, a frequency bandwidth, a subcarrier spacing, a waveform,
a reference signal pattern, a cyclic prefix overhead setting, or
some combination thereof for each communication configuration of
the multiple communication configurations. In a further embodiment,
the method 600 includes receiving the configuration information via
signaling (e.g., RRC signaling). In certain embodiments, the method
600 includes receiving resource information corresponding to the
communication configuration. In some embodiments, the multiple
communication configurations include communication configurations
selected from the group including enhanced mobile broad band, ultra
reliable and low latency communication, and massive machine type
communication.
In various embodiments, the method 600 includes receiving selection
information via signaling for selecting the communication
configuration. In some embodiments, the method 600 includes
dynamically selects the communication configuration. In one
embodiment, the communication configuration includes an uplink
communication configuration corresponding to an uplink control
channel, an uplink data channel, or some combination thereof. In a
further embodiment, the communication configuration includes a
downlink communication configuration corresponding to a downlink
control channel, a downlink data channel, or some combination
thereof. In various embodiments, the configuration information
includes a resource allocation configuration, a transmission mode
configuration, or some combination thereof.
FIG. 7 is a schematic flow chart diagram illustrating one
embodiment of a method 700 for communication configuration
selection. In some embodiments, the method 700 is performed by an
apparatus, such as the base unit 104. In certain embodiments, the
method 700 may be performed by a processor executing program code,
for example, a microcontroller, a microprocessor, a CPU, a GPU, an
auxiliary processing unit, a FPGA, or the like.
The method 700 may include transmitting 702 configuration
information for multiple communication configurations (e.g., such
as shown in Tables 1 and 2). In certain embodiments, the
configuration information corresponds to services (e.g., eMBB,
URLLC, MMC) having different performance requirements, and the
performance requirements may include latency, reliability, peak
data rate, efficiency overhead, control overhead, system capacity,
or some combination thereof. The method 700 also includes
communicating 704 (e.g., transmitting and/or receiving) data using
a selected communication configuration of the multiple
communication configurations.
In one embodiment, the configuration information includes a time
duration, a frequency bandwidth, a subcarrier spacing, a waveform,
a reference signal pattern, a cyclic prefix overhead setting, or
some combination thereof for each communication configuration of
the multiple communication configurations. In a further embodiment,
the method 700 includes transmitting the configuration information
via signaling. In certain embodiments, the method 700 includes
transmitting resource information corresponding to the
communication configuration. In some embodiments, the multiple
communication configurations include communication configurations
selected from the group including enhanced mobile broad band, ultra
reliable and low latency communication, and massive machine type
communication.
In various embodiments, the method 700 includes selecting the
selected communication configuration. In some embodiments, the
method 700 includes transmitting information indicating the
selected communication configuration. In one embodiment, the
communication configuration includes an uplink communication
configuration corresponding to an uplink control channel, an uplink
data channel, or some combination thereof. In a further embodiment,
the communication configuration includes a downlink communication
configuration corresponding to a downlink control channel, a
downlink data channel, or some combination thereof. In various
embodiments, the configuration information includes a resource
allocation configuration, a transmission mode configuration, or
some combination thereof.
Embodiments may be practiced in other specific forms. The described
embodiments are to be considered in all respects only as
illustrative and not restrictive. The scope of the invention is,
therefore, indicated by the appended claims rather than by the
foregoing description. All changes which come within the meaning
and range of equivalency of the claims are to be embraced within
their scope.
* * * * *